High vs Main Profile

[moola]

Does High Profile require more CPU power than Main when encoding and decoding? Is it more complex?

[admin]

High Profile allows room for more encoder features to be used, than Main Profile. So the answer to your questions is "sometimes". Sometimes a High Profile encode will require more processing power to encode/decode than a Main Profile encode, but not always. Profiles are more to indicate the type of applications that the video will be used for (eg. streaming, portable players, Blu-ray, HDTV ...).

Main Profile is actually a subset of High Profile (but not the other way around), so something that is said to be encoded with compatibility for Main will always be compatible for High (but again, not the other way around).

Remember there's also the concept of Levels, which restrict the encoder properties (resolution, bitrate ...) that can be used, so actually, Levels are a better indication of performance requirements for decoding than profiles.

The charts on Wikipedia shows what each of the profiles and levels are pretty clearly:

http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC

[moola]

thank you

[moola]

Could you tell me what Level within High profile is required for true Blu-ray disk movie quality?

[UncasMS]

4 and 4.1 are very common

[moola]

And H.264 has 17 profile sets is that correct?

[admin]

Yes, 17. All 17 are listed on the Wikipedia page I linked too.

[moola]

When developers talk in terms of H.264 "implementation" of the encoding and decoding...what are they referring to? Profile? Level? What factors are the taking in to account? What makes one implementation worse/better than another?

[admin]

I would say the efficiency would be the key factor.

[moola]

so what factors contribute to a good implementation or a bad one? what determines the resolution and picture quality - is implementation only determined by profile and level?

[moola]

nudge

[helixhamin]

High Profile allows room for more encoder features to be used, than Main Profile. So the answer to your questions is "sometimes". Sometimes a High Profile encode will require more processing power to encode/decode than a Main Profile encode, but not always. Profiles are more to indicate the type of applications that the video will be used for (eg. streaming, portable players, Blu-ray, HDTV ...).

Main Profile is actually a subset of High Profile (but not the other way around), so something that is said to be encoded with compatibility for Main will always be compatible for High (but again, not the other way around).

Remember there's also the concept of Levels, which restrict the encoder properties (resolution, bitrate ...) that can be used, so actually, Levels are a better indication of performance requirements for decoding than profiles.

The charts on Wikipedia shows what each of the profiles and levels are pretty clearly:

Is there anywhere we can get sampling of these 17 different video types for end device testing of the h.264 standard?